Output Tests

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Output Tests

This is an example of how you can test the output stream of student code. 
This test makes sure the student's code prints "Hello World".  It assumes the student's file name is Example.java.  Replace the Example.main(null) call with whatever you student's file name is. 
Note:  This code converts the output to all lowercase and removes spaces to compare against the correct value.
Grading Tests:
import org.junit.Before;
import org.junit.After;
import org.junit.Test;
import static org.junit.Assert.*;
import java.io.*;
​
​
public class CodingRoomsUnitTests {
    
    private final PrintStream standardOut = System.out;
    private final ByteArrayOutputStream outputStreamCaptor = new ByteArrayOutputStream();
​
    @Before
    public void setUp() {
        System.setOut(new PrintStream(outputStreamCaptor));
    }
​
    @After
    public void tearDown() {
        System.setOut(standardOut);
    }
​
    @Test
    public void testDefaultCase() {
        Example.main(null);
        assertEquals("Hello World".toLowerCase().trim().replace(" ", ""), outputStreamCaptor.toString().toLowerCase().trim().replace(" ", ""));
    }    
}
Sample Solution:
Example.java
public class Example
{
    public static void main(String[] args)
    {
        System.out.println("Hello World");
    }
}

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